Re: [PATCH 01/10] Add driver auto probing for x86 features

From: Jean Delvare
Date: Fri Dec 09 2011 - 15:28:50 EST


On Fri, 09 Dec 2011 12:24:47 -0800, Andi Kleen wrote:
>
> > Can you guarantee that there is no asymmetric system already working
> > today?
>
> I used to have an asymmetric system myself, but we generally subset the
> CPU feature
> flags to be the same everywhere and I didn't change any per CPU stepping
> checks
> as they were there.
>
> > If you can't, then your approach could cause a regression. This
> > is why I am asking for an API change to let drivers pass a specific CPU
> > to x86_match_cpu(). There are at least two drivers who would take
> > benefit of this. Your patch set is supposed to only add driver
> > auto-loading, and while cleaning up the code in the process is nice, I
> > think you should avoid driver behavior changes, these are out of scope
> > for such a patch set.
>
> I undoed that change to the coretemp driver

Thanks.

> and there's no other AFAIK.

via-cputemp was affected as well.

> Generally most drivers only check the boot cpu.

--
Jean Delvare
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